System and method for providing power to a mining operation

ABSTRACT

A system for employing gravity to provide electrical power for mining operations in a mine includes a battery configured to power an electric vehicle. The vehicle includes a kinetic energy capture system that can charge the battery as the vehicle conveys a loaded vehicle down a ramp from an ore face to a chamber. Traveling down the ramp produces a surplus charge in the battery due to a weight differential between a loaded vehicle traveling down a ramp producing more energy via the kinetic energy capture system than energy used by the vehicle to convey the empty vehicle up the ramp to the ore face. A discharging device disposed in the chamber is configured to discharge the surplus energy out of the battery and into the mine&#39;s power grid. One or multiple trips between the ore face and the chamber may fully charge the battery.

BACKGROUND OF THE INVENTION

The present invention relates generally to providing electrical power toa mine. Specifically, electrical power captured by a kinetic energycapture system associated with an electric vehicle may charge the onboard battery of the vehicle, which may then be discharged into themine's power grid.

Subsurface mining operations may consume large amounts of energy. Themine power grid may provide electrical power to many different systems,including but not limited to environmental controls, ore and minerelevators, and mining vehicles. Power costs may be a significant portionof the operating costs of the mine. For mine operations controlled froma subsurface location, transmitting the power from the surface may beinefficient.

An additional factor in providing power to a mine is controllingemissions, which must be evacuated from the mine to maintain a habitableatmosphere. Emissions in the mine may prove expensive to control. Forexample, mine vehicles may generate emissions. Generating power at asubsurface location may produce unwanted or expensive to controlemissions. Mine vehicles may also generate unwanted heat, which may bedisadvantageous in an already hot mine.

Systems and methods that can produce inexpensive power in a mine withoutcontributing emissions or heat to the mine environment would provideoperational and cost advantages.

SUMMARY OF THE INVENTION

Various embodiments of systems and methods for using kinetic energycapture technologies to charge battery-powered mining vehicles and, dueto weight differences between transporting a load such as ore, wasterock, and/or equipment, downhill from an ore face to a chamber anddriving an empty vehicle back uphill to the ore face, provide an excesscharge to the batteries. The batteries will eventually reach a maximumcharged state and may be dissipated by discharging the battery's chargeinto the mine's power grid to run various operational systems, likeenvironmental controls, conveyors, lights, and any other type of miningoperations system.

In one aspect, the invention provides a system for employing gravity toprovide electrical power for mining operations in a mine, wherein themine having a shaft extending downward from the earth's surface to achamber containing a power grid for powering the mining operations, adeposit having an ore face positioned between the chamber and theearth's surface, and a ramp extending at an incline between the ore faceto the chamber. The system comprises a battery associated with azero-emissions vehicle, wherein the battery is configured to be chargedby a kinetic energy capture system associated with the vehicle when thezero-emissions vehicle travels on the ramp from the ore face to thechamber while carrying a load. The system also includes a dischargingdevice disposed in the chamber, wherein the discharging device isconfigured to discharge energy out of the battery and into the powergrid when the battery is attached to the discharging device.

In another aspect, the invention provides a system for employing gravityto provide electrical power for mining operations in a mine, wherein themine has a shaft extending downward from the earth's surface to achamber containing a power grid for powering the mining operations, adeposit having an ore face positioned between the chamber and theearth's surface, and a ramp extending between the ore face and thechamber. The system comprises a zero-emissions vehicle including akinetic energy capture system and a battery configured to power thezero-emissions vehicle when attached to the zero-emissions vehicle. Thebattery is configured to receive power from the kinetic energy capturesystem when the zero-emissions vehicle travels down the ramp carrying aload from the ore face to the chamber. The system further includes adischarging device configured to discharge energy out of the battery andinto the power grid when the battery is attached to the dischargingdevice.

In another aspect, the invention provides a method for powering a miningoperation, the method comprising the steps of (1) loading a vehiclepowered by a battery with a load from a deposit, wherein the vehicle isconfigured to capture the kinetic energy of the vehicle to charge thebattery; (2) driving the loaded vehicle down a ramp to a chamber; (3)capturing kinetic energy while driving the loaded vehicle; (4) chargingthe battery to a predetermined discharge level using captured kineticenergy; and (5) discharging the charged battery to a predetermined uselevel.

Other systems, methods, features and advantages of the invention willbe, or will become, apparent to one of ordinary skill in the art uponexamination of the following figures and detailed description. It isintended that all such additional systems, methods, features andadvantages be included within this description and this summary, bewithin the scope of the invention, and be protected by the followingclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be better understood with reference to the followingdrawings and description. The components in the figures are notnecessarily to scale, emphasis instead being placed upon illustratingthe principles of the invention. Moreover, in the figures, likereference numerals designate corresponding parts throughout thedifferent views.

FIG. 1 shows an embodiment of a mining operation;

FIG. 2 shows an embodiment of various mining operation elements that maybe powered by a power grid in a mine;

FIG. 3 shows a flowchart of an embodiment of a method of using gravityto power a mining operation;

FIG. 4 shows a schematic embodiment of how gravity can be used toprovide energy for capture;

FIG. 5 shows an embodiment of how a gravity capture system can be usedin a mining setting;

FIG. 6 shows an embodiment of discharging captured energy to a minepower grid;

FIG. 7 shows another embodiment of discharging captured energy to a minepower grid;

FIG. 8 shows an embodiment of a vehicle for use in mining operations,where the vehicle is equipped to capture kinetic energy;

FIG. 9 shows a schematic embodiment of a kinetic energy capture systemfor use in a vehicle.

DETAILED DESCRIPTION

Providing power to sub-surface mining operations can present variouschallenges. For deep mines, transmitting the energy from the surface maybe inefficient, and generating the power at depth may generate toxicemissions that are costly to dissipate and control. Various embodimentsof systems and methods for using kinetic energy capture technologies tocharge battery-powered mining vehicles and, due to weight differencesbetween transporting ore from an ore face to a chamber and driving anempty vehicle back to the ore face, provide an excess charge to thebatteries. The batteries will eventually reach a maximum charged stateand may be dissipated by discharging the battery's charge into themine's power grid.

FIG. 1 shows an embodiment of the operations of a shaft mine 100. Mine100 includes an ore deposit 110 disposed beneath a surface 101. Thecomponents of shaft mine 100 may be used for reference in discussing thesystems and methods for providing power to the mine, an embodiment ofwhich is shown in FIG. 3. Shaft mine 100 may be any type of mine knownin the art that involves transporting ore within the mine, particularlythose mines that are configured so that ore is transported by a vehiclefrom a higher elevation to a lower elevation within a mine. Shaft mine100 has been simplified from many different possible mine configurationsfor the sake of clarity in this description.

In the following discussion, directional and relative terms may be used.“Above”, “over”, “high”, and “higher” refer to positions closer tosurface 101 than another relative position. “Below”, “beneath”, “under”,“low”, and “lower” refer to positions further away from surface 101 thananother relative position. “Up” refers to a direction towards surface101. “Down” refers to a direction away from surface 101.

An excavation such as a vertical shaft 104 or an incline shaft (notshown) extends from surface 101 to a collection level 103. Shaft 104 maybe any type of shaft known in the art, such as a vertical shaft.Collection level 103 may be positioned at any depth within the mine, butin some embodiments, collection level 103 may be positioned belowdeposit 110 as shown in FIG. 1.

Shaft 104 may terminate at collection level 103 in or proximate achamber 120. Chamber 120 may be a room formed in the mine and configuredto house various mining operations and controls. Chamber 120 may containor house various aspects of the mining operation, such as containing anore receiving and/or processing station and/or access to the mine powergrid or other mining operation control systems. In some embodiments,collection level 103 may form a floor or part of a floor of chamber 120.

A hoist 107 may be associated with shaft 104. Hoist 107 may bepositioned at surface 101. Shaft 104 may be provided with a mine cage109 or ore elevator to transport ore to surface 101. Hoist 107 may beconfigured to lift mine cage 109 using known methods. As shown in FIG.1, mine cage 109 may open into chamber 120. Chamber 120 may includeother provisions for handling ore, such as a crusher 180 that may beconfigured to crush the ore extracted from deposit 110 into smallerpieces so that mine cage 109 may be filled more efficiently and/or themore may be moved more easily. A conveyor system such as conveyor system182 may be provided to move ore from ore transportation vehicles likeunloading vehicle 170 into crusher 180 and/or mine cage 109.

In some embodiments, the extraction operations occur at an ore face 112.As is known in the art, extraction operations may include any method ofremoving ore from the ore face, such as cutting, drilling, and blasting.Extracted ore may then be loaded onto a vehicle for transportation to asecondary location, such as collection level 103 for conveyance tosurface 101. The secondary location may include additional processing,such as crushing the ore in crusher 180 for easier conveyance to surface101. In some embodiments, the secondary location may be chamber 120, andcollection level 103 may be a floor in chamber 120.

In some mines, ore face 112 may be positioned closer to surface 101 thanthe secondary location such as chamber 120. The height 128 of ore face112 above collection level may be any height. In some embodiments,height 128 may be any height sufficient to place collection levelentirely beneath deposit 110. In some embodiments, height 128 may be anyheight between surface 101 and a bottom of deposit 110.

An ore load such as ore load 111 may be transported from ore face 112 tochamber 120 in one or more vehicles such as loaded vehicle 150. Becauseore face 112 and the extraction operation occurs above chamber 120,loaded vehicle 150 may convey ore load 111 to chamber 120 by drivingdown a ramp such as ramp 125. Ramps within mines are well known.

Ramp 125 may be a straight, curved, or multilevel path extending betweenan extraction point and the collection level. In the embodiment shown inFIG. 1, ramp 125 is shown as a simple straight path which is wide enoughto allow for vehicles to simultaneously travel towards and away from theextraction point at ore face 112. Ramp 125 may have a length 127 asmeasured along a surface of ramp 125 between ore face 112 and collectionlevel 103. Length 127 may be any length sufficient to connect ore face112 and collection level. In some embodiments, length 127 may range fromseveral hundred feet to several miles.

Ramp 125 may have a grade defined by ramp angle 129. Ramp angle 129 maybe any angle that permits a vehicle to easily travel on the surface oframp 125. In some embodiments, the grade of ramp 125 may range from a 6%grade to a 20% grade. In some embodiments, the grade may be even higher,such as when rail cars are being utilized. The grade may be up to 30% insuch embodiments. In other embodiments, the grade of ramp 125 may belower than 6% or greater than 30%.

Various systems within the mine may draw power from the mine's powergrid. FIG. 2 shows examples of some systems within a mine that may berun by the mine's power grid. The examples in FIG. 2 are not acomprehensive list for use in every mine, and some mines may usedifferent combinations of these electrical systems, additionalelectrical systems, fewer electrical systems, or different systemsentirely. Examples of such systems include the ventilation system formaintaining appropriate air quality within the mine. Lights in the minemay be run from the power grid. Climate control, such as airconditioning, fans, and/or heaters may draw power from the power grid.Pumps for controlling water within the mine or for directing water to anore face for assisting in extraction operations may be powered by thepower grid. Conveyors for moving ore, equipment, and/or personnel withinthe mine may use power from the power grid. A crusher for breaking oredown into smaller or more uniform pieces than extraction can produce maybe part of the mine's electrically powered operations.

The energy requirements for running a mining operation may be intensiveand expensive. FIG. 3 shows an embodiment of a method 300 that uses theconfiguration of a mine such as mine 100 where the ore is conveyed froman extraction point down a ramp to a collection level in a vehicle toproduce energy for powering the mining operations. A first step 310 ofmethod 300 includes loading a transport vehicle with ore at theextraction point. In one embodiment, such as the embodiment shown inFIG. 1, vehicle 150 has been provided an ore load 111 at ore face 112.Load 111 may be anything capable of increasing the mass of the transportvehicle, including but not limited to ore, waste rock, equipment,personnel, and/or combinations thereof. Ore face 112 is the extractionpoint for mine 100. The loading of ore into a vehicle may be achievedusing any method known in the art. For example, heavy machinery such asa bucket loader may introduce ore into the vehicle. In another example,a conveyor may transfer extracted ore from the extraction point to thetransport vehicle. The conveyer may be a separate component of the mineor the conveyor may be integrated into the extraction machinery. Inanother example, miners may manually load ore into the transportvehicle. The weight of the vehicle at this point is the weight of theunloaded vehicle plus the weight of the ore load.

A second step 320 of method 300 includes driving the vehicle down a rampto a collection point. In the embodiment of mine 100 shown in FIG. 1,ramp 125 connects the ore face 112 or extraction point with thecollection level 103, which may be a floor of chamber 120. In someembodiments, the vehicle is a zero emissions vehicle. In suchembodiments, the vehicle may be a battery-powered electric vehicle. Thevehicle's onboard battery may be removable and rechargeable. In someembodiments, the vehicle's onboard battery may be configured for rapidand easy extraction and installation into the vehicles so that any minermay be able to perform these battery swapping functions. For example,the battery may be part of a modular system that provides an easilychanged battery and a housing configured to withstand harsh mineconditions. An example of a suitable battery and battery system is themodular battery and bus system described in US Patent ApplicationPublication Number 2015/0086825 to Huff et al., which patent applicationis incorporated herein by reference in its entirety. Additionally,appropriate batteries and battery systems may be obtained from ArtisanVehicle Systems of Camarillo, Calif.

A third step 330 of method 300 includes capturing the kinetic energy ofthe vehicle as the loaded vehicle travels down the ramp from theextraction point to the collection level. Third step 330 also includescharging the onboard battery with that captured kinetic energy. Kineticenergy capture systems are well known in the art. Examples of kineticexergy capture systems include regenerative braking systems, which usereverse motion of the wheels of a vehicle to turn the electric motorinto a generator, and piezoelectric systems, which use the kineticenergy of a system to squeeze crystals to produce electricity. Thecaptured kinetic energy is converted into electrical energy and storedin the vehicle's onboard battery. Technologies for charging an onboardbattery using captured and converted kinetic energy are also well knownin the art, such as those systems associated with regenerative brakingsystems in electric and hybrid vehicles.

A fourth step 340 of method 300 includes unloading the ore from thevehicle to reduce the weight of the vehicle. This step is shown in FIG.1, where unloading vehicle 170 is positioned on collection level 103 inchamber 120. The unloading may occur using any method known in the art.In the embodiment shown in FIG. 1, unloading vehicle 170 is dumping theore from a bed like a dump truck onto a conveyor 182. In otherembodiments, heavy machinery may be used to remove the lore load fromunloading vehicle 170, or the ore may be removed from unloading vehicle170 and placed into a bin, pile, or other storage location to awaitadditional processing or additional transportation. Removing the orefrom the vehicle reduces the weight of the vehicle. In some embodiments,the weight reduction may be significant, with the ore load weighing athousand pounds or more. In other embodiments, the weight reduction maybe less, such as when the ore load weight less than a thousand pounds.At this point in the method, the weight of the vehicle is only theweight of the unloaded vehicle.

A fifth step 350 of method 300 includes determining the charge or stateof the onboard battery. This may be accomplished using any method knownin the art. For example, a dashboard in the vehicle may display thisinformation in real time with constant measuring of the battery charge.The vehicle operator may then determine if the battery has reached thepredetermined discharge level. Such constant measuring of a batterycharge level is well known and common in electric and hybrid vehicles.In other embodiments, a controller associated with the battery may beequipped to measure the battery charge and for remote communication,such as wireless or wireline communication. The controller may be anytype of mechanism known in the art capable of performing thesefunctions. For example, the controller may be a computer that includes aprocesser and an associated memory as well as a transmitter, receiver,or transceiver. The transceiver may be configured to transmit theinformation using any known method and communication protocol, such asradio signals, Bluetooth signals, optical signals, combinations of thesesignals, or the like. When within chamber 120 or in another collectionlocation, the controller associated with the battery may broadcast thecharge to a receiving station, such as a computer, handheld device, orother mechanism configured to receive information from the controller.The receiving station may include a display so that a technician maymonitor the incoming data regarding the battery. The receiving stationmay include programming so that the receiving station sends or emits asignal when the charge of the battery has reached a predetermined level.The signal may be received by a technician or the vehicle operator.

Obtaining the battery charge information in fifth step 350 is a decisionpoint in method 300. If the battery has not yet reached a predeterminedlevel such as a maximum desired charge, then the method moves to sixthstep 360. Sixth step 360 includes driving the unloaded, lighter vehicleback up the ramp to the extraction point. In FIG. 1, sixth step 360 isshown where unloaded vehicle 160 is driving up ramp 125 in the oppositedirection as loaded vehicle 150. Unloaded vehicle 160 uses battery powerto propel the vehicle up ramp 125 to the extraction point, ore face 112.During this operation, some portion of the battery charge of the onboardbattery will be consumed. However, due to the weight difference betweena loaded vehicle and an unloaded vehicle, the consumption of power fromthe battery required to drive an unloaded vehicle up the ramp is lessthan the amount of energy captured by a kinetic energy capture systemwhile driving a loaded vehicle down the ramp. This aspect of the methodfor providing power to a mine is discussed in greater detail below withrespect to FIG. 5.

If, however, the battery has reached a predetermined discharge level orstate, such as a maximum desired charge, method 300 moves to seventhstep 370. Seventh step 370 involves removing the charged battery fromthe vehicle. Seventh step 370 may be accomplished using any method knownin the art. Seventh step 370 may be accomplished quickly and easily ifthe onboard battery is a modular battery such as is available fromArtisan Vehicle Systems. In some embodiments, seventh step 370 may beoptional, as the battery need not be removed from the vehicle in orderto proceed to the eighth step 375 in method 300: discharging the batteryinto the mine's power grid.

Eighth step 375 of method 300 includes attaching the battery to adischarging device, such as discharging device 175 shown in FIG. 1.Discharging the battery transfers the stored energy in the battery tothe mine's power grid via the discharging device. Transferring theenergy from the battery into the mine's power grid may be accomplishedusing any method known in the art. The power grid may contain energystorage devices like capacitors and batteries to receive and store thetransferred energy.

In the embodiment shown in FIG. 1, a discharging battery 190 is attachedto discharging device 175 using a cable. In other embodiments,discharging device 175 may be configured so that discharging battery 190may inserted into a receiving slot in discharging device 175. In theembodiment shown in FIG. 1, discharging battery 190 has been removedfrom a vehicle. In other embodiments, discharging battery 190 may remainwithin or otherwise attached to the vehicle, while discharging battery190 is attached to discharging device 175, such as through a portdisposed on or through the body of the vehicle.

Discharging device 175 may be any type of discharging device known inthe art. In some embodiments, discharging device 175 may include a gridconnection, one or more networks (e.g., the Internet), a remote terminal(e.g., a personal computer), and a remote data store. The dischargingdevice 175 may support various AC systems. For example, dischargingdevice 175 may support an AC system associated with an AC supply. Forexample, discharging device 175 may support various voltages, current,power, frequencies (e.g., 50 Hz, 60 Hz), number of phases, and the like.In the example, discharging device 175 may support a 480/600 volt ACvoltage.

Similarly, discharging device 175 may support various DC systems. Forexample, discharging device 175 may support a DC system associated witha battery. For example, discharging device 175 may support a 480 volt DCvoltage. In other examples, discharging device 175 may support a 240volt DC voltage. In some examples, discharging device 175 may support a65 kW DC power output. In other examples, discharging device 175 maysupport a 100 kW DC power output.

The bi-directional converter of discharging device 175 may use varioustypes of converter topologies including, for example, buck, boost,buck-boost, and the like. Similarly, the bi-directional converter mayuse various types of inverter topologies including, for example, agrid-tie inverter system, a square wave, modified square wave, modifiedsine wave, pure sine wave, and the like. The topologies used in thebi-directional converter may support a bi-directional function. As usedherein, bi-directional DC/AC converter may include a converterconfigured to (1) convert from the DC system to the AC system and (2)convert from the AC system to the DC system. In some embodiments, thebi-directional converter may include an AC to DC converter forconverting from the AC system to the DC system and a DC to AC inverterfor converting from the DC system to the AC system. In otherembodiments, a single converter is used to convert between the AC andthe DC systems.

Additional details regarding one possible embodiment of a dischargingdevice for use in a method for providing power to a mine such as method300 are described in U.S. patent application Ser. No. 14/529,853 (filedby Huff et al. on Oct. 31, 2014) which is incorporated herein byreference in its entirety.

The battery is discharged into the mine's power grid until the batterycharge has reached a minimum acceptable charge or a predetermined uselevel. This process may take several minutes to several hours, dependingupon the capacity of the battery and the charged state of the battery.The minimum acceptable charge may be any charge capable of powering thevehicle back up the ramp to the extraction point. In some embodiments,the minimum acceptable charge may be a 20% battery charge. In otherembodiments, the minimum acceptable charge may be higher or lower than20% depending upon various factors including but not limited to thebattery capacity, the consumption rate of power by the vehicle, thelength of the ramp, and other factors.

The discharging device may be configured to also provide power to anonboard battery. For example, if a battery charge were to fall below theminimum acceptable charge, such as due to unanticipated system losses oroperator error, the onboard battery may be charged to any desired levelusing the discharging device.

Once the battery has been discharged to the minimum acceptable level,the battery can be disconnected from the discharging device. In someembodiments, a ninth step 380 of method 300 may then be executed. Ninthstep 380 includes attaching the minimum acceptable charge battery to anunloaded vehicle. In some embodiments, ninth step 380 involvesreattaching the discharged battery to the same vehicle from which thedischarged battery was removed. In such embodiments, the unloadedvehicle may remain proximate the battery for the duration of discharge.Such embodiments are depicted and discussed in greater detail below withrespect to FIG. 6. In other embodiments, ninth step 380 includesproviding the discharged battery to a different vehicle. In suchembodiments, multiple vehicles are in use in the mine at any given time.Therefore, the discharged battery may be stored proximate thedischarging device until a vehicle with a fully charged onboard batteryarrives at the discharging device. The fully charged onboard battery ofthe vehicle may be removed from the vehicle for discharging while thewaiting discharged battery is connected to the unloaded vehicle so thatthe unloaded vehicle may resume operations immediately. Such embodimentsare depicted and discussed in greater detail below with respect to FIG.7. As such, in some embodiments, eighth step 375 and ninth step 380 mayoccur simultaneously.

Once ninth step 380 has been completed, the process continues at sixthstep 360. The unloaded vehicle with the minimum acceptable chargebattery uses the battery charge to drive back up the ramp to resumemethod 300 at first step 310. Method 300 may thus continue for manyiterations of charging the onboard battery using a kinetic energycapture system and discharging the battery into the mine's power grid.

Method 300 employs the weight differential between the loaded vehicleand the unloaded vehicle to advantage in charging the battery. FIG. 4 isa diagram that shows conceptually how transporting a heavier mass from aheight to a lower level and a lighter mass from the lower level back tothe height may produce energy. First mass 410 is shown in a firstposition 411 at a height H. The gravitational force g gives first mass410 a weight. At height H, first mass 410 has a first potential energy,and a stored energy system 430 associated with first mass 410 may have afirst state. Stored energy system 430 may be a capacitor or a battery.

Moving first mass 410 down to a second position 415 requires theapplication of a force to fight the acceleration due to gravity so thatfirst mass 410 moves through height H to second, lower position 415 in acontrolled fashion and does not just fall in an uncontrolled manner.That force may be captured and converted to electrical energy using anyknown kinetic energy capture system, such as regenerative braking orpiezoelectric technologies. The stored energy system 430 may increaseits charge to second state 435 as the energy is captured.

Stored energy system 430 may then be associated with a second mass 420that is positioned in third position 421. Third position 421 is at thesame height as second position 415. However, second mass 420 is lighterthan first mass 410. Second mass 420 may use energy from stored energysystem 430 to raise second weight 420 from third position 421 to afourth position 425. Fourth position 425 is at height H above thirdposition 421. Energy is extracted from stored energy system 430 toovercome gravity to lift second mass 420 to height H. However, becausesecond mass 420 is lighter than first mass 410, the amount of energyexpended to raise second mass 420 to height H may be less than theamount of energy captured by stored energy system 430 when controllingthe lowering of first, heavier mass 410 from height H to second position415. Therefore, stored energy system 430 may be left with a surplusenergy charge 450. Thus, lowering a heavy weight and raising a lightweight through the same distance may produce a net surplus of storedenergy. The net surplus 450 may be small but non-negligible. Therefore,multiple iterations of lowering heavy masses and raising light massesmay eventually fully charge stored energy system 430.

For a more concrete example of this principle, FIG. 5 shows a trip cycleor a charging cycle in mine 100 that produces a surplus charge in arechargeable onboard battery 514 according to an embodiment of method300 shown in FIG. 3. In an initial position 501 proximate ore face 112,according to first step 310, a load 505 of ore is loaded into vehicle510. Because vehicle 510 is loaded with ore, vehicle 510 has a loadedweight 529. Loaded weight 529 may be any weight and represents theweight of vehicle 510 plus the weight of load 505.

Vehicle 510 is powered by battery 514, which is removably attached tovehicle 510. Battery 514 may be any type of rechargeable batterysuitable for use in a mine vehicle.

At initial point 501, battery 514 has an initial state 515 with aninitial charge 517. Initial charge 517 may be any charge that battery514 is capable of maintaining and which will power vehicle 510 frominitial point or high point 501 proximate ore face 112 to collectionlocation 103. Initial charge 517 is also less than a full charge so thatbattery 517 is capable of accepting an additional charge from a kineticenergy capture system associated with vehicle 510. In some embodiments,initial charge 517 may be a 20% charge of a typical electric vehiclebattery. In other embodiments, the initial charge 517 may be different.

In the embodiments shown in FIG. 5 and FIG. 1, collection location 103is a floor of chamber 120. Initial point 501 is connected to collectionlocation 103 by ramp 125. Ramp 125 has height 128 and a grade 129.Following second method step 320, vehicle 510 transports load 505 downramp 125 to a low position 503, which is proximate collection location103.

As vehicle 510 travels down ramp 125 according to third step 330, akinetic energy capture system associated with vehicle 510 convertsselected movements of vehicle 510 from mechanical motion into electricalenergy and stores that captured electrical energy in battery 514. Theselected movements of vehicle 510 may be any movement of vehicle 510,but may particularly be those movements associate with controllingvehicle 510 against the pull of gravity down ramp 125. For example, theselected movement may be braking to slow vehicle 510 as vehicle 510travels down ramp 125. In such an embodiment, kinetic energy capturesystem may include a regenerative braking system, which may be any typeof regenerative braking system known in the art. In another embodiment,the selected movement may be the movement of a coil spring in one ormore struts associated with the wheels of vehicle 510. In such anembodiment, the kinetic energy capture system may include a system forconverting the energy released by the coiling and uncoiling of thesprings of the struts as vehicle 510 passes over uneven ground and/orwhile ore is loaded into the vehicle.

Once vehicle 510 reaches low point 503, the charge in battery 514 hasincreased to a second battery state 520 due to the kinetic energycapture. The added charge 521 from the trip down ramp 125 may varydepending upon various factors, such as the length of ramp 125, theslope of ramp 125, the grade of ramp 125, the efficiency of the kineticenergy capture system, the loaded weight 529 of vehicle 510, and otherfactors.

Once vehicle 510 has reached low point 503, load 505 may be unloadedfrom vehicle 510 according to fourth step 340 of method 300. Removingload 505 from vehicle 510 reduces the weight of vehicle 510 to anunloaded weight 532, which is exclusively the weight of vehicle 510.Unloaded weight 532 is less than loaded weight 529. In some embodimentsunloaded weight 532 may be hundreds or thousands of pounds lighter thanloaded weight 529, depending upon the size of load 505. In otherembodiments, unloaded weight 532 may be other weight differentials.

Vehicle 510 may proceed to execute sixth step 360 of method 300 andtravel back up ramp 125 to initial position 501 proximate ore face 112.Battery 514 provides the energy to the motor of vehicle 510 for themovement back up ramp 125. However, vehicle 510 is now at unloadedweight 532, which may be significantly less than loaded weight 529.Battery 514 may discharge while traveling back up ramp 125 as thevehicle's electric motor draws power from the battery 514 to propelvehicle 510 up the ramp. Because vehicle 510 is lighter when unloaded,the energy expenditure for traveling back up ramp 125 may not exceed theamount of added charge 521.

When vehicle 510 reaches initial position 501 to receive another load ofore, battery 514 may be in a third battery state 530. Third batterystate 530 includes a net surplus charge 525. Surplus charge 525 is lessthan added charge 521 because some energy from battery 514 was used toconvey vehicle 510 up ramp 125. However, surplus charge 525 is greaterthan initial charge 517, because the amount of energy captured by thekinetic energy capture system while vehicle 510 drives down ramp 125with a heavy load 505 is greater than the amount of energy expended byconveying lighter vehicle 510 without a load back up ramp 125. Battery514 is left with a net surplus energy charge.

FIG. 5 shows one trip cycle: driving a loaded vehicle 510 down ramp 125,unloading vehicle 510, and driving an unloaded vehicle 510 back up ramp125 back to ore face 112. As shown in FIG. 5, one trip cycle may producea net surplus energy charge but may not fully charge battery 514.Therefore, vehicle 510 may repeat first step 310 through sixth step 360of method 300 for additional trip cycles in order to reach a fullycharged state. The number of trip cycles may be two or more. In someembodiments, a fully charged state may be a 100% charge of battery 514.In other embodiments, a fully charged state may be any charge at which adischarge of energy into the mine's power grid may be efficient orotherwise desirable. In other embodiments, a single trip cycle may fullycharge battery 514, such as if ramp 125 is very long or very steep, ifload 505 is very heavy, or if battery 514 has low capacity.

FIG. 6 shows an embodiment of how energy may be extracted from battery514 and transferred to the power grid. Once truck 510 has enteredchamber 120, battery 514 may be tested to determine its charge, asdiscussed above in fifth step 350 as shown in FIG. 3. If the charge hasreached a predetermined discharge level, such as 100% or greater than80% or any other level selected to be sufficient to efficientlydischarge battery 514, battery 514 may be removed from truck 510 andassociated with discharging system 175 where battery 514 enters adischarging state 635. As discussed above, discharging system 175 may bea bidirectional charging system. Discharging system 175 is electricallylinked to the mine's power grid. As power is drained from battery 514due to the discharging, power is fed to the mine power grid throughdischarging system 175. The mine power grid may include capacitors,rechargeable batteries, or other provisions for receiving the dischargedpower from batter 514 via discharging system 175. The mine power gridmay then use the discharged power to run the mine electrical systems,such as lights, climate control systems, ventilation systems, and thelike.

Once battery 514 has been discharged to a minimal acceptable chargestate 640, battery 514 may be disconnected from discharging system 175and reconnected to vehicle 510. In some embodiments, the minimalacceptable charge may be a 20% charge. In other embodiments, the minimalacceptable charge may be the charge sufficient to drive vehicle 510 fromchamber 120 to ore face 112 and at least partially back down the rampafter vehicle 510 has been reloaded with ore at ore face 112.

In the embodiment shown in FIG. 6, vehicle 510 waits in chamber 120while battery 514 discharges to the minimal acceptable charge. Thedischarging process may require that battery 514 be connected todischarging system 175 for an hour or more. In those embodiments,vehicle 510 would be idle for the duration of discharge. Such idlenessmay be undesirable to the mining operation as inefficient, especiallywhen vehicle resources may be limited.

FIG. 7 shows an alternate embodiment of how energy may be extracted frombattery 514 and transferred to the power grid while avoiding idling avehicle. Once vehicle 510 has entered chamber 120, battery 514 may betested to determine its charge, as discussed above in fifth step 350 asshown in FIG. 3. If the charge has reached a predetermined level, suchas 100% charge, greater than 80% charge, or any other level selected tobe sufficient, battery 514 may be removed from truck 510 and associatedwith discharging system 175 where battery 514 enters a dischargingstate. As in the embodiment shown in FIG. 6, discharging system 175 iselectrically linked to the mine's power grid. As power is drained frombattery 514 due to the discharging, power is fed to the mine power gridthrough discharging system 175. The mine power grid may includecapacitors, rechargeable batteries, or other provisions for receivingthe discharged power from batter 514 via discharging system 175. Themine power grid may then use the discharged power to run the mineelectrical systems, such as lights, climate control systems, ventilationsystems, and the like. Battery 514 is then discharged to a minimalacceptable charge. In some embodiments, the minimal acceptable chargemay be a 20% charge. In other embodiments, the minimal acceptable chargemay be the charge sufficient to drive vehicle 510 from chamber 120 toore face 112 and at least partially back down the ramp after vehicle 510has been reloaded with ore at ore face 112. In other embodiments, theminimal acceptable charge may be higher or lower than a 20% charge.

While battery 514 is discharging to a minimal acceptable charge state, asecond battery 714 already at the minimal acceptable charge state 640 isretrieved from a storage location in chamber 120 or otherwise proximatedischarging system 175. Second battery 714 is then connected to vehicle510. Vehicle 510 may then travel back up ramp 125 to the ore face underthe power provided by second battery 714 while the first battery 514 isdischarging. In some embodiments, one spare battery such as secondbattery 714 may be provided. In other embodiments, more than one sparebattery may be provided, particularly in embodiments where dischargingsystem 175 may simultaneously discharge multiple batteries.

In the embodiments discussed above, shaft 104 is a vertical shaft. Inother embodiments, an inclined shaft may be provided between the surfaceand the ore deposit. In such embodiments, the iterative kinetic energycapture process discussed above may be used even when initially buildingthe ramp between the surface and the ore deposit as well as duringongoing mining operations.

FIG. 8 shows an embodiment of a zero emissions vehicle 810 suitable foruse in a subterranean mine such as mine 100 and for implementing variousembodiments of the method for providing power to a mine such as method300 discussed above. Vehicle 810 may include an electric motor 800 whichis powered by an onboard battery 814. Onboard battery 814 may be anytype of battery known in the art, such as the batteries discussed abovelike battery 514. Vehicle 810 is provided with various standardvehicular mechanisms and capacities, such as a passenger cab 813 forreceiving one or more operators, a vehicle bed 850 configured with a bedcompartment 851. Vehicle 810 may be sized and shaped to operatecomfortably in most or all areas of the subterranean mine, withsufficient width and height clearances to maneuver within intended usespaces. Vehicle 810 may be modular so that various parts may betransported from the surface within mine cage 109, shown in FIG. 1.Vehicle 810 may be configured to be assembled in chamber 120.

Bed compartment 851 may be sized and shaped to receive a load of ore.The size and shape of bed compartment 851 may vary depending upon thetype of ore, the desired amount of ore per load, and the intended mannerof loading. For example, bed compartment 851 is configured as anopen-top bed so that ore may be loaded into bed compartment 851 fromabove, such as with a loader such as a bucket loader.

In some embodiments, vehicle 810 may be provided with an optional hitchwagon 855 so that additional ore per carry may be conveyed by vehicle810 without impinging upon maneuvering clearances for operating vehicle810 within the intended areas of the mine. Hitch wagon 855 may include ahitch 858, which may be any type of towing hitch known in the artcapable of securely connecting hitch wagon 855 to vehicle 810 whilepulling an intended load. Hitch wagon 855 may be configured in a similarmanner to bed compartment 851, with a wagon compartment 859 configuredto receive a load of ore in a similar fashion and in similar quantitiesas bed compartment 851. In other embodiments, wagon compartment 859 maybe a different size and/or shape and/or configuration than bedcompartment 851.

Vehicle 810 is provided with ground contacting elements for moving thevehicle 810 along the ground, such as a continuous track or, as shown inthe embodiment in FIG. 8, one or more wheels on axles. The type ofground contacting element may be selected based upon the mine terrainand the intended load weights. The wheels may be solid or may includeinflatable tires. Vehicle 810 may include any number of wheels, such asthree, four, five, six, or more depending upon the intended use of thevehicle, such as the type of maneuvering, the intended load, and thetraction capabilities of the wheel. In the embodiment shown in FIG. 8,four wheels are provided, including a front driver side wheel 837, afront passenger side wheel 836, and a rear wheel 839. A fourth rearwheel corresponding to rear wheel 839 is also provided but not shown inFIG. 8. All of these wheels may be the same size, or the front wheelsmay be a different size from the rear wheels.

All wheels may be mounted onto axles. For example, front wheels 837 and836 may be mounted on an axle 835 associated with a drive train 838.Axle 835 and/or front wheel 837 may be attached to the body of vehicle810 using any method known in the art. For example, a first strut 830and a second strut 832 may be provided to attach axle 835 and/or frontwheel 837 to the chassis of vehicle 810. First strut 830 and secondstrut 832 may be any type of strut known in the art configured to resistcompression, such as a MacPherson strut employing coil springs. Drivetrain 838 may transfer force from the engine 800 to the wheels using anymethod known in the art.

Optional hitch wagon 855 may also include one or more wheels such aswheel 857. Wheel 857 may be mounted on an axle. Wheel 857 may or may notbe linked to drive train 838.

Vehicle 810 is provided with a kinetic energy capture system 820 so thatthe method of providing power to the mine power grid discussed above maybe implemented. Kinetic energy capture system 820 may be any type ofkinetic energy capture system known in the art, such as a regenerativebraking system. However, in other embodiments, kinetic energy capturesystem 820 may include a regenerative braking system as well as otherkinetic energy capture systems. For example, first strut 830 and secondstrut 832 may be linked to a system that captures the energy generatedby the spring motion of the struts as vehicle 810 passes over unevenground.

FIG. 9 shows a schematic embodiment of a regenerative braking systemthat may be used as at least a part of a kinetic energy capture systemfor vehicle 810. In this embodiment, a vehicle may be provided with fourwheels: a first wheel 920, a second wheel 921, a third wheel 922, and afourth wheel 923. Each wheel may be associated with an electric motor900 via a drive train, axles, a gear box 917, or other known systems.Rechargeable battery 814 is also associated with electric motor 900.Battery 814 may be connected to motor 900 directly or battery 814 may beindirectly connected to motor 900 via a controller 915 and/or aninverter 910. Controller 915 may be any type of processer known in theart, such as an onboard computer system. Controller 915 may be providedwith memory, such as RAM, ROM, flash memory, or any other type of memoryknown in the art. The memory may contain software configured to controlthe discharge of energy from battery 814 and the recharging of battery814 via the regenerative braking process.

Regenerative braking is well known. Instead of slowing the wheels of avehicle down by clamping the wheels and dissipating the energy from thatclamping process as heat, the wheels are turned in the oppositedirection to the drive direction. By turning the wheels in this oppositedirection, motor 900 transitions from an energy consuming device to anenergy creating device. Effectively, motor 900 becomes a generator thatcaptures the kinetic energy of the turning of the wheels and convertsthat energy into electricity. Typically, motor 900 produces and usesalternating current. Inverter 910 then further converts that generatedelectricity into direct current, a form of energy that can be stored inbattery 814. In this manner, a regenerative braking system may be usedto charge battery 814. In some embodiments, inverter 910 may beunnecessary if motor 900 uses direct current.

The iterative process of surplus power generation described above is notlimited to mining, but may be used in any endeavor where a transport maybe loaded for a downhill trip and unloaded for an uphill trip at asufficient weight differential between the loaded and unloaded vehicleto provide surplus energy generation on a trip cycle. Industries thatmay benefit from an iterative kinetic energy capture system thatexploits potential energy in operations include but are not limited topower generation, construction, manufacturing, and shuttling operationssuch as funicular or tramp operations where the cars may be heavilyloaded in the downward direction only during selected times, such as theend of a work day. In any of these operations, the surplus power may bedischarged into a power grid or into reserved batteries for use in thesystem.

For example, the system above may be adapted for use in hydroelectricpower generation. Vehicle 810, discussed above, includes groundcontacting elements, in this case, wheels, that are configured todirectly contact the ground. In other embodiments, vehicle 810 may beconfigured to operate on rails. In such rail embodiments, vehicle 810may be capable of operating at steeper grades than wheeled vehicles. Forexample, in some hydroelectric power generating operations, reservoirssituated at a relatively high elevation are used to generate electricalpower by drawing the water down into a chamber to run turbines or otherexergy extraction machines, and is then pumped back up into thereservoir. Bores are excavated between the chamber and the reservoir.Some bores may be at a 30% grade, while other bores may be at higher orlower grades. A light railed vehicle may be used to excavate the bore.The vehicle may be unloaded in the chamber and then driven up the boreon a rack and pinion system to provide stability for the steep grade.The railed vehicle may be loaded with waste rock and/or earth, then sentback down the bore with the heavy load. Following the principlesdiscussed above, the light railed vehicle may be configured with abattery and kinetic energy capture system that charges the battery. Asiterative trips are made up and down the bore, the weight differentialbetween the empty and the loaded light railed vehicle can charge thebattery to a maximum desired capacity. The chamber may be provided witha discharging system as discussed above, so that additional batteriesand/or the chamber power grid may be charged using the surplus energygenerated during the excavation process.

While various embodiments of the invention have been described, thedescription is intended to be exemplary, rather than limiting and itwill be apparent to those of ordinary skill in the art that many moreembodiments and implementations are possible that are within the scopeof the invention. Any element of any embodiment may be substituted foranother element of any other embodiment or added to another embodimentexcept where specifically excluded. Accordingly, the invention is not tobe restricted except in light of the attached claims and theirequivalents. Also, various modifications and changes may be made withinthe scope of the attached claims.

The invention claimed is:
 1. A system for employing gravity to provideelectrical power for mining operations in a mine, wherein the mine has ashaft extending downward from the earth's surface to a chambercontaining a power grid for powering the mining operations, and adeposit having an ore face positioned between the chamber and theearth's surface, such that the chamber is disposed downwardly from theore face, the system comprising: a ramp extending between the ore faceand the chamber; a zero-emissions vehicle including a kinetic energycapture system; a first battery on the zero-emissions vehicle, whereinthe first battery is configured to power the zero-emissions vehicle andto be charged by the kinetic energy capture system when thezero-emissions vehicle travels down the ramp from the ore face to thechamber while the zero-emissions vehicle carries a load; a dischargingdevice disposed in the chamber, wherein the discharging device isconfigured to discharge energy out of the first battery and into thepower grid only when the first battery is attached to the dischargingdevice in the chamber.
 2. The system of claim 1, wherein the firstbattery is configured to receive a net surplus energy charge from thekinetic energy capture system when the zero-emissions vehicle makes atrip cycle, wherein a trip cycle is a loaded trip down the ramp to thechamber and an unloaded trip up the ramp back to the deposit.
 3. Thesystem of claim 2, wherein the first battery is attached to thedischarging device after at least one trip cycle.
 4. The system of claim2, wherein the first battery is attached to the discharging device aftermore than two trip cycles.
 5. The system of claim 1, wherein thedischarging device is a bidirectional charger.
 6. The system of claim 1further comprising at least one additional minimally charged battery sothat the first battery on the vehicle may be replaced with the minimallycharged battery when the first battery is attached to the dischargingdevice.
 7. The system of claim 1, wherein the kinetic energy capturesystem is a regenerative braking system.
 8. A system for employinggravity to provide electrical power for mining operations in a mine,wherein the mine has a shaft extending downward from the earth's surfaceto a chamber and a deposit having an ore face positioned between thechamber and the earth's surface, such that the chamber is disposeddownwardly from the ore face, the system comprising: a ramp extendingbetween the ore face and the chamber; a power grid for powering themining operations, wherein the power grid is disposed within thechamber; a zero-emissions vehicle including a kinetic energy capturesystem; a battery on the zero-emissions vehicle and configured to powerthe zero-emissions vehicle when attached to the zero-emissions vehicleand to receive power from the kinetic energy capture system when thezero-emissions vehicle travels down the ramp carrying a load from theore face to the chamber; and a discharging device configured todischarge energy out of the battery and into the power grid only whenthe first battery is attached to the discharging device in the chamber.9. The system of claim 8 further comprising a charging cycle, whereinthe charging cycle comprises the zero-emissions vehicle conveying a loadof ore down the ramp from the ore face to the chamber and thezero-emissions vehicle driving up the ramp from the chamber to the oreface while the zero-emissions vehicle is unloaded, wherein the loadedzero-emissions vehicle is heavier when the zero-emissions vehicle isconveying a load than when the unloaded zero-emissions vehicle isunloaded, and wherein the battery is configured to receive a net surplusenergy charge from the charging cycle.
 10. The system of claim 9,wherein the net surplus energy charge from a charging cycle issufficient to charge the battery to a maximum desired charge.
 11. Thesystem of claim 9, wherein the net surplus energy charge from more thanone charging cycle is sufficient to charge the battery to a maximumdesired charge.
 12. The system of claim 11, wherein the maximum desiredcharge is a 100 percent charge.
 13. The system of claim 9, wherein thebattery is attached to the discharging device after at least onecharging cycle.
 14. The system of claim 9, wherein the battery isattached to the discharging device after more than two charging cycles.15. The system of claim 8, wherein the battery is configured to bedischarged to a minimum acceptable charge by the discharging device. 16.The system of claim 15, wherein the minimum acceptable charge is a 20percent charge.
 17. A system for employing gravity to provide electricalpower for mining operations in a mine, wherein the mine has a shaftextending downward from the earth's surface and a deposit having an oreface positioned below the earth's surface, the system comprising: achamber positioned at a bottom of the shaft , wherein the chamber ispositioned further below the earth's surface than the ore face ispositioned; a ramp extending between the ore face and the chamber; apower grid for powering the mining operations, wherein the power grid isdisposed within the chamber; a zero-emissions vehicle including akinetic energy capture system; a first battery on the zero-emissionsvehicle and configured to power the zero-emissions vehicle when attachedto the zero-emissions vehicle and to receive power from the kineticenergy capture system when the zero-emissions vehicle travels down theramp carrying a load from the ore face to the chamber; and a dischargingdevice configured to discharge energy out of the first battery and intothe power grid only when the first battery is attached to thedischarging device in the chamber.
 18. The system of claim 17 furthercomprising a charging cycle, wherein the charging cycle comprises thezero-emissions vehicle conveying a load of ore down the ramp from theore face to the chamber and the zero-emissions vehicle driving up theramp from the chamber to the ore face while the zero-emissions vehicleis unloaded, wherein the zero-emissions vehicle is heavier when thezero-emissions vehicle is conveying a load than when the zero-emissionsvehicle is unloaded, and wherein the battery is configured to receive anet surplus energy charge from the charging cycle.
 19. The system ofclaim 18, wherein the net surplus energy charge from a charging cycle issufficient to charge the first battery to a maximum desired charge. 20.The system of claim 18, wherein the net surplus energy charge from morethan one charging cycle is sufficient to charge the first battery to amaximum desired charge.
 21. The system of claim 20, wherein the maximumdesired charge is a 100 percent charge.
 22. The system of claim 18,wherein the first battery is attached to the discharging device after atleast one charging cycle.
 23. The system of claim 18, wherein the firstbattery is attached to the discharging device after more than twocharging cycles.
 24. The system of claim 17, wherein the first batteryis configured to be discharged to a minimum acceptable charge by thedischarging device.
 25. The system of claim 17 further comprising atleast one additional minimally charged battery so that the first batteryon the vehicle may be replaced with the minimally charged battery whenthe first battery is attached to the discharging device.